The adjustable regulator is used so that you can have the burner on full and still be able to adjust the flow of gas. My setup is a 100lb propane tank connected to a Ransome burner through a ball type gas valve. The gas comes through the regulator which I usually have set at 10 psi. The valve is mostly for shutting the gas flow on or off except the 1st cycle where I use the valve to turn the burner up in gradual steps. From the valve the gas goes through the orifice which is a fixed size(sorry, I don't remember the size and the kiln is not where I am but I can get that later). This sequence determines the BTU value of the burner. 500K BTU sounds like a lot for Raku but that would be a maximum output under ideal conditions so the regulator combined w/the orifice size really determine the output of the burner.

I hope this is not overly detailed. I have used many different Raku kilns and burners but they all work on the same principle.

I will get the orifice size for my burner so we can do the math but this weekend it is camping with the sun-in-laws and the grandchildren so it will be a few days.

Alright folks, so I've done a couple more firings, since I've widened both ports.

I did one this past Monday, to test the kiln, for the firing I would be doing with my students this Friday.

It went well. The glazes reached maturity, and in a good amount of time. The wares themselves, aren't exactly where I wanted them, but that was due to my rushing the reduction, not because of the kiln.

So this afternoon, my Art club did our second annual firing. Last year's firing went well, but the kiln stalled, and some of the glazes didn't mature. The students still had fun though.

This year, the kiln gods smiled upon us. The kiln performed beautifully, the glazes reached maturity, and we had some great reduction. The students were super psyched with the results, but sad, that I wouldn't let them take them home, until after they've been in the display case a while.

We actually did two firings, and the second one took almost no time at all, due at least in part, to the port modifications.

I've got one more firing to do this weekend, as we didn't have time to fire all the student's projects. So I will do those, and possibly even my couple pots, that didn't reduce in the way I wanted earlier in the week.